Graphical program to display a testbed block diagram with real-time data on an IBM personal computer

A graphical program called TESTBED was written in Pascal in summer 1985 for NASA Lewis Research Center, Cleveland, Ohio. TESTBED displays on an IBM Personal Computer/XT a block diagram of the DC testbed for the power management and distribution system for the space station. When the testbed, which will contain photovoltaic arrays, batteries, and loads, is deployed in the field, it will be permanently connected to the IBM PC/XT via direct memory access. Sensors attached to the testbed in the field will continually collect and updata data in real time. The program will superimpose the real-time data on the block diagram of the testbed displayed on the screen of the IBM PC/XT. The program uses procedures contained in Metawindow, a software package of graphics utilities written by Metagraphics Corp., Mountain View, California.     

A FORTRAN program for multivariate survival analysis on the personal computer

In this paper a FORTRAN program is presented for multivariate survival or life table regression analysis in a competing risks' situation. The relevant failure rate (for example, a particular disease or mortality rate) is modelled as a log-linear function of a vector of (possibly time-dependent) explanatory variables. The explanatory variables may also include the variable time itself, which is useful for parameterizing piecewise exponential time-to-failure distributions in a Gompertz-like or Weibull-like way as a more efficient alternative to Cox's proportional hazards model. Maximum likelihood estimates of the coefficients of the log-linear relationship are obtained from the iterative Newton-Raphson method. The program runs on a personal computer under DOS; running time is quite acceptable, even for large samples.     

A fast computer program for conformational analysis

We describe a program, called SOBALCAN, that enables us to compute very quickly the rotation hypersurface of a flexible molecule in the “ soft-sphere” approximation. Only those conformations in which the overlap of spheres associated to all pairs of non-bonded atoms is less than a prefixed threshold are computed.     

Analysing isoenzyme band patterns using similarity coefficients: a personal computer program

A computer program in Fortran 77 was developed to analyse the isoenzyme patterns of trypanosomes isolated from African sleeping sickness patients, to allow biochemical relationships between populations of trypanosomes from different hosts and geographic areas to be elucidated. However, the generality of the design allows it to be used with presence/absence data from a variety of sources, including DNA fingerprints. The program reads in isoenzyme band patterns from an ASCII file and calculates a matrix of similarity coefficients. Four different similarity measures are offered, suitable for presence/absence data from a range of organisms and experimental procedures. The matrix of similarity values produced is suitable for analysis by ordination methods including principal coordinates analysis, and the production of dendrograms and icicle plots using SPSS/PC+.     

A computer program for thin walled frame analysis

The paper presents a general purpose computer program capable of analysing any planar frame made up of members which can be categorised as thin-walled members. The approach is based on Vlasov's theory which accunts for coupling between torsion and bending actions. The topic is gaining importance due to the improved techniques of producing cold-formed steel sections which have much higher strength than normal steels. The program is in the form of single-array storage which makes its application easy even by a practicing engineer who cannot go into the details of Vlasov's theory. The program is illustrated by means of an example with complete information about input and output for the particular problem.     

A personal computer program using a 4-component logit for the evaluation of ELISA calibration curves with unknown asymptotic values

A BASIC program is described for the calculation of ELISA calibration curves using a 4-component logit for the linearisation of the sigmoidal shape. The difficulty of estimating the four logit parameters without knowledge of upper and lower asymptotic values is overcome by statistical analysis of the experimental data. The program is run on an IBM-PC and the curves are plotted by a HP7475A plotter.     

A computer program for three dimensional analysis of buildings

A special purpose computer program for the linear three dimensional analyses of building structures for gravity, lateral and earthquake loads is presented. The building is idealized as consisting of a series of rigid jointed rectangular frame or frame-shearwall substructures interconnected through a rigid floor diaphragm. Finite joint sizes, shear deformations and axial deformation of columns are considered. Three dimensional frequencies and mode shapes are evaluated and a response spectrum approach is used for the dynamic analysis. A front-end processor accepts input data in a conversational mode and in free format. Data input is speeded up by taking advantage of the repetitive nature of frame dimensions, member sizes and loadings.     

NHPPREG: a computer program for the analysis of nonhomogeneous Poisson process data with covariates.

A program written in C is described which finds maximum likelihood estimates of regression coefficients and other relevant parameters for a point process with covariates. The data are assumed to come from a Poisson point process and may be modelled, at the user's choice, either totally parametrically or semi-parametrically. Furthermore, extra Poisson variation may be introduced, in both the parametric and semi-parametric approach, by the device of random effects. The work closely follows the theory developed by Lawless (1987).     

A simplified visual inspection system using a personal computer

For a practical visual inspection system, data processing in real time, flexibility for variety of products, and cost performance have been required. This article describes a simplified visual inspection system that has well-balanced performance that meets these requirements. Inspection data processing by software makes the inspection system flexible. Development of a simplified pattern matching method based on limiting the inspection within the area pointed by an user and direct memory access of binary image data performs a high speed inspection function. By using a personal computer as a processor of this system, a cost effective inspection system is realized.     

A computer program for the analysis of matched case-control studies

The use of regression methods for matched epidemiologic studies is discussed. A computer program is given for use in analysis of 1-1 and 1-R matched case-control data as well as the more general stratified analysis, where m cases are matched with n controls in each of K strata. The program permits variable matching ratios. An illustration is given.     

Electrocardiogram simulation using a personal computer

A personal computer with a digital-to-analog converter is used as an electrocardiogram simulator. A TurboPascal procedure, given the heart rate, rhythm, and ST segment levels, generates the voltages for Leads II and V5. A simple circuit reduces the voltages to the physiologic range and smoothes the waveforms, removing the staircase effects of digitalization. The procedure can be manually controlled using a software interface or driven by other programs for use in a full-scale operating room simulator.     

Ballerinas generated by a personal computer

Beautiful 3-D figures of ballerinas have been generated by a non-professional artist using a personal computer with commercially available ray-tracing software and metaballs. This paper describes how these beautiful artistic creations have been drawn using very limited computational tools.     

An investigation of data entry methods with a personal computer

The features of three methods of data entry were investigated and a trial of them was carried out using operators with differing amounts of keyboard experience. The first method was a simple system of character entry using a word processing package, and the second and third systems were written in a commercial data base language; one was designed to possess limited intelligence, the other moderate intelligence. The amount of time and computing expertise required to set up each method increased in parallel with its sophistication. The most sophisticated method offered theoretical advantages of reduced error rates and increased keying rates but these were not realized in practice. The limited intelligence method, in which data were entered into a screen image of the record form, was fastest overall and was most popular with all users. This method together with verification by dual keying will provide a convenient, rapid, and high fidelity method of data entry. The simplest method was found to be adequate for short forms but incurred high error rates with longer forms.     

A computer program for the structural analysis of welded tubular joints with RHS chords

A computer program is presented for the analysis of statically loaded structural hollow section (SHS) lattice girder joints having one compression bracing member and one tension bracing member welded to a rectangular hollow section (RHS) chord member. A set of failure modes has been established for such joints, having either gapped or overlapped bracings at the connection to the chord face. To these failure modes the yield line method has been applied in order to provide an assessment of the limiting joint strength. The computer program, based upon the analyses of these failure models and written in Fortran, can hence be used to estimate the yield or ultimate joint strength, with a data input of 30 joint parameters. The program and the theories proposed have been verified by comparison with the results of 150 joint tests, conducted both in isolation and in complete girders, at testing centres in three different countries.